Boring type mining head having eccentric wedge



c. H. SNYDER 2,776,123

BORING TYPE MINING HEAD HAVING ECCENTRIC WEDGE Jan. 1, 1957 2 Sheets-Sheet 1 Filed Oct. 25, 1952 iai a IN VEN TOR. (Z/F1 4? M W052 M 2% 6/5 Afiorng/ Jan. 1, 1957 C. H. SNYDER BORING TYPE MINING HEAD HAVING ECCENTRIC WEDGE Filed 001;. 23, 1952 2 Sheets-Sheet 2 7/5 A if oa -neg United States Patent BORING TYPE MINING HEAD HAVING ECCENTRIC WEDGE Clifford H. Snyder, Dormont, Pa., assignor to The Colin-oi Company, New Lexington, ()hio, a corporation of Ohio Application October 23, 1952, Serial No. 316,419

Claims. (Cl. 262-7) This invention relates generally to mining machines, and more particularly to eccentric mining heads for use on large augers for high wall mining or on the front of continuous mining machine.

The principal object of this invention is the provision of an eccentric mining head that is constructed so that it may be of large diameter for use with large augers for high wall mining in removing the coal or other material, or it may be made as a part of a continuous mining machine requiring a series of rotary eccentric cutting arms on the forepart thereof, for the purpose of continuously mining a tunnel, and wherein the eccentric heads cut a tunnel materially larger than the cross-sectional size of the machine, and while doing so, will remove the coal or other material in large chunks, thereby increasing the general size of the coal mined.

Another object of this invention is the provision of an eccentric arm for digging coal or other material which will bore in and wedge out large chunks of coal from the surface in cutting its way through the material. The wedging action is produced by chipping a wide swath or kerf, and as the head progresses and produces a space wherein a wedging action can take place in forcing the coal laterally of the auger into the space cut out, and then allowing it to fall in the path of the machine or the auger and be conveyed rearwardly in fairly large chunks or lumps.

Large chunks of coal are cut out by providing an eccentric arm, with a pilot bit, mounted in the center of rotation and capable of rotating with the arm or independently of the arm, and the arm being provided with a sector or a sectional portion of a cylindrical drum and having teeth spaced therearound, and the maximum area cut is determined by the eccentricity of the arm. The cutting continues with a forward feed with a swath or kerf encircling the cavity produced by the pilot bit. The cylindrical portion of the drum provides adequate cavity and the central pilot section is provided with a wedge for forcing the coal laterally outwardly into the cavity and thereby breaking off large chunks which are in one instance received by the large augers and conveyed rearwardly. If the heads are somewhat smaller and are mounted on a continuous mining machine the coal is not fractured into small chunks, but is conveyed in large chunks rearwardly through the machine.

The method for obtaining large chunks of coal in this manner is to cut the concentric kerfs, the center kerf being the cavity produced by the pilot bit and its cam wedge and the outer kerf is produced by the outer end of the eccentric or unbalanced arm, cutting in a circular path to form a kerf and provide a cylindrical cavity. This space is for the wedge to move the coal laterally outwardly thereinto so that the coal will break off along the vertical cleavage planes parallel to the face being cut. Generally speaking, the cleavage planes of coal runvertically and horizontally with the vertical cleavage planes being disposed at right angles to one another.

The cleavage planes are parallel with the rotary action 2,77'6,i23 Patented Jan. 1, i957 and are substantially normal thereto. This natural condition of coal makes it ideal to remove it under the process comprising the principles of mining as disclosed in this application.

Other objects and advantages are hereinafter in the following description and claims.

The accompanying drawings show, for the purpose of exemplification, without limiting the invention and claims thereto, certain practical embodiments of the invention wherein:

Fig. 1 is a front elevation of an eccentric cutter arm comprising this invention.

Fig. 2 is a top plan view of the structure indicated in Fig. 1, showing the adaptation of the unbalanced arm to an auger.

Fig. 3 is a front elevation of a modified form of an eccentric rotary cutting arm which is made in two parts.

Fig. 4 is a plan view of the structure illustrated in Fig. 3, showing the application of the arm to a large auger.

Fig. 5 is a vertical section of the forward part of a continuous mining machine showing a plurality of forwardly projecting shafts having eccentric arms comprising this invention mounted thereon.

Fig. 6 is a front elevation of a machine such as illustrated in Fig. 5.

Fig. 7 is a sectional view illustrating the eccentric arm similar to that shown in Figs. 1 and 2 on a continuous mining machine.

Referring to Figs. 1 and 2 of the drawings the coal cutting head comprises the arm 1, the shaft 2 and the cam or wedge member 3. The arm 1 iuterfits with the wedge 3 as shown on the drawings and has an opening that slides over and is attached by the key 2 with the shaft 2 as shown in Fig. 2. The wedge member 3 may be keyed or otherwise secured to the shaft 2 as by means of the pins 3. The outer end of the shaft 2 has a removable pilot bit 4 interlocked therewith by the pin 4'. Thus there is no relative rotary motion between the shaft 2 and the members 1, 3 and 4.

The shaft 2 is provided with the enlarged shoulder 5 fastened to the end of the conical plate 6 which in turn is removably secured to the end of the tubular shaft 9 by means of the screws 7. This conical plate structure constitutes a socket means by which the arm 1, the shaft 2 and the wedge 3 are detachable from the shaft 9. The shaft 9 also carries a large auger 10 having the teeth 11 on its front or leading edge for the purpose of gathering and conveying coal rearwardly.

The large hollow shaft 9 not only aids in the formation of the large auger member 10, but is preferable to employ the hollow tubular shaft 9 as a fluid conduit. Because of the size, the shaft 9 is used for the purpose of aiding in the construction and support of the large auger, and also for the purpose of conveying fluids that are to be carried to the head such as water, which may be discharged to wet the coal and keep the dust down. In place of water, it is sometimes preferable to employ oil, such as a used automobile oil, or other light lubricant that not only keeps the dust down, but increases the value of the fuel itself. Nozzles, such as indicated at 12, may be employed to project dust settling fluids over the entire cutting face.

Referring now to Figs. 1 to 4, the eccentric arms 1 and 13 are substantially the same, each being provided with a cylindrical section 14 having a series of cutting teeth 15 on the forward edge and a series of teeth 16 on both sides of this cylindrical section. It will be noted that the cylindrical section 14 reduces in cross-section towards its trailing end to provide clearance between the cylindrical head and the cavity. The eccentric or un- 3 balanced arms 1 and 13 are also provided with forward cutting teeth 17.

Eccentric arm 13 is detachably secured to the large tubular shaft 9 by the socket means. The conical plate has an outwardly extending sleeve 18 on which the socket means of the arm 13 is mounted. The central shaft 2 of Figs. 3 and 4 is extended through the shaft 9 and is journaled in the sleeve 18, where it passes therethrough for the purpose of providing a different and variable speed to the rotary movement of the pilot bit 4 and the wedge or cam member 3 relative to that of the eccentric arm 13 and the shaft 9 on which it is mounted. A conical end 8 on the shaft 9 is nested in the conical plate 6 and fastened thereto by the bolts 7.

The shaft 2 may be rotated at a different speed from that of the shaft 9, thus permitting the control of the speed of the cam 3 to be independent of the control of the speed of the cylindrical section 14. This permits one to vary the relative speed and rotation of these members, so as to produce a new method of mining the coal that they dig.

The sector 14 may be rotated at a uniform speed, whereas the wedging cam 3 may be rotated in timed relation, so that it does not interfere with the coal between the two until a predetermined advancement has been made, at which time the speed of the shaft 2 may be increased so as to cause the cam 3 to swing and function at a different speed than that of the sector and thus laterally push out a larger chunk of coal. In this way, the shaft 2 may be speeded up or retarded, operated intermittently or maintained at a constant speed somewhat faster or slower than that of the sector 14. The sector 14 may be rotated at a non-uniform rate of speed in place of varying the speed of the central shaft 2 for the purpose of obtaining larger chunks of coal. The cam or wedge 3 on the shaft 2 and the auger 10 on the shaft 9 may be operated by a single gear structure similar to that illustrated in Fig. 5.

Cams and arms similar to that illustrated at 3 and 13 with the central portion being rotated independently of the sector, are applied with detachable socket means to apply them to a continuous mining machine such as shown in Fig. 5, wherein the cam members 3 and the pilot bits 4 are mounted on the shafts 2 which pass through the rotary gear mechanism in the forepart of the gear boxes to the rotary gear mechanism as illustrated by the gears and 21. The sector portion 14 of each of the eccentric heads have a socket means mounted on the tubular shaft members 22 which extend through suitable bearings and are connected with the gear train as illustrated at 23 and 24. The gear trains 23 and 24 should be maintained in timed relation as disclosed in previous structures of this character in the prior art. However, the gear trains 20 and 21 may be independently controlled so as to be properly timed for the purpose of wedging out large chunks of coal as previously stated.

The mining machine 25, shown in Fig. 5, has an upper gear box 26 and a lower gear box 27, and the lower part of the frame 28 is provided with a conveyor member 29 which interrupts a portion of the floor scraping blade 30 and is provided with a continuous conveyor chain which gathers the coal and conveys it rearwardly. The face of the lower gear box is provided with additional bearing supports such as indicated at 31, and the gear box is also provided with suitable bearings such as indicated in the drawings.

The shaft 22 of the upper gear box has an eccentric 32 mounted thereon, which operates the cutter members 33 that cut the kerfs at the top of the cavity or tunnel being mined as indicated in Fig. 6.

Referring now to Figs. 6 and 7, the mining machine shown is provided with a cutting head, such as illustrated in Figs. 1 and 2, wherein the wedging cam member 3 is connected to the arm 1 and the sector thus rotates in unison with the cam. As noted in Fig. 1 and Fig. 6, the cam is positioned so that its largest area commences at the space of the smallest cross-section of the sector at which time it is most effective in wedging the coal from the face. The wedges 3 are smooth and continuous, there being teeth at the position of the greatest radius of the cam. The machine as disclosed in Figs. 6 and 7, is a similar structure to that disclosed in Fig. 5 with the exception that in Fig. 5, an extra set of gears has to be provided for the dual rotating shafts 2.

As shown in Fig. 7, the machine is supported on endless tracks. The upper and lower sets of gears 23 and 24 are timed with each other through the shaft 34 and the gear train 35 and 36 and the universal coupling and shaft 37 and the shaft 38 to the gear train and the gear box 3 and returned through the shaft 40 and its universal coupling as indicated at 41 to the upper gear train 23. Two fiuid motors may be provided for driving these gears which will be fed through the worm 42 to the worm gear 43 on the shaft 34. Thus, both the upper and lower rows of the cutting head members 1 are operated in timed sequence.

The same is true of the structure as shown in Fig. 5 wherein the gears 23 and 24 are operated in timed rela tion through the same type of timing gear structure.

The continuous mining machine 25 is provided with the hydraulic generator 44 operated by the electric motor 45, and the output of the hydraulic generator 44 is effective through the tubular system as indicated at 46 to operate the hydraulic motor that drives the worm gear 42.

Each of the dual rotary head members, such as illustrated at Figs. 1 and 2 are eccentric head members as indicated at Fig. 7, are all mounted by socket means on the forwardly projecting shafts in front of the gear boxes of the machine as illustrated in Fig. 6, arms are proportioned so that they will not interfere with one another, yet they will mine a complete tunnel as indicated at 47, which is materially larger in size than the machine 25. The lower part of the machine is provided with the ear flaps 48 for guiding the coal and throwing it back on the blade 30 where it is moved by the outer eccentric arm members to the conveyer 29 and thence conveyed to the rear of the machine.

In Fig. 7, the machine is not provided with the eccentric members 32 for cutting the kerfs at the top of the mine, but is provided with the scraping blade 50 for this purpose, which blade is mounted and may be collapsed to provide the maneuverability of the machine within the tunnel that it cuts.

The flaps and the blades may be moved within the dimensions of the machine and when the eccentrically mounted arms are folded in as illustrated in Fig. 6, the machine may be maneuvered to dig laterally in the tunnel it has cut. The blade 30 is raised or lowered to dig up and down.

In the structure shown in Figs. 5 and 7 the upper gear box is shown independent of the lower gear box so as to be capable of being raised a limited amount from the lower gear box to enable the machine to cut a deeper vein of coal or follow the variations in thickness of a vein being mined.

Both the auger and the machine are provided with the cam and the cylindrical sector on an unbalanced or eccentric arm, whether on an auger or a machine, provides a new mode of digging coal.

With the cam wedge member tapered from the apex adjacent the pilot bit 4 and by providing a sector for an eccentric digging head, with a larger forward cutting portion and a smaller trailing portion, one is enabled to produce a deep concentric kerf around the hole bored by the pilot bit and the action of the cam 3, whether indedependently operated or not, will shove the coal laterally by its eccentric action. This lateral action, in combination with the eccentric arm, breaks off large pieces of coal. The coal fractures following the cleavage lines parallel to the face. These chunks of coal are apt to lay flat on the conveyor and can be carried readily in large chunks to the rear of the machines.

I claim:

1. A coal mining head comprising a rotary shaft, a digging arm eccentrically mounted on said shaft, an eccentric wedge projecting forwardly from said shaft beyond said digging arm, a pilot bit beyond the end of said eccentric wedge, and an arcuate digging section on said digging arm substantially coextensive with and in spaced relation from said eccentric wedge to cut an annular coaxial kerf into which the eccentric wedge laterally breaks the coal.

2. The structure of claim 1 characterized in that the outer surface of said arcuate digging section is cylindrical.

3. The structure of claim 1 characterized in that said arcuate digging section tapers from the leading edge to provide clearance.

4. The structure of claim 1 characterized in that said eccentric wedge has its greatest eccentric dimension substantially opposite the rear end of said arcuate digging section.

5. The structure of claim 1 characterized in that said eccentric wedge increases in cross-sectional diameter from the pilot bit toward said digging arm.

6. The structure of claim 1 which also includes a second rotary shaft projecting from the end of the first rotary shaft and supporting said eccentric wedge and pilot bit for rotation independently of said digging arm.

7. The structure of claim 1 which also includes an auger on said rotary shaft.

8. The structure of claim 1 characterized in that said rotary shaft extends from the forward end of a mining machine.

9. The structure of claim 1 characterized in that there are a plurality of said rotary shafts extending from the forward end of a mining machine and each of said shafts is provided with an eccentrically mounted digging arm to cut a tunnel larger than the machine.

10. A coal mining machine comprising a mobile body having a plurality of pairs of concentric rotary shafts extending from the front thereof, a digging arm eccentrically mounted on the outer shaft of each pair, an eccentric wedge mounted on the inner shaft of each pair outwardly of said eccentric arm, a pilot bit mounted at the outer end of each eccentric wedge, and an arcuate digging section on each digging arm in spaced relation from said eccentric wedge to cut an annular coaxial kerf into which the eccentric wedge laterally breaks the coal.

References Cited in the file of this patent UNITED STATES PATENTS 504,180 Stanley Aug. 29, 1893 957,957 Hirst May 17, 1910 1,273,869 Joy July 30, 1918 1,603,621 McKinlay Oct. 19, 1926 2,118,490 Challacombe May 24, 1938 2,250,670 Joy July 29, 1941 2,384,397 Ramsay Sept. 4, 1945 2,546,899 McCarthy Mar. 27, 1951 2,562,841 Compton July 31, 1951 FOREIGN PATENTS 981,860 France May 31, 1951 OTHER REFERENCES Mining Congress Journal, May 1951, page 23. 

